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About transmissible spongiform encephalopathy unit (TSE)

TSE unit, through the National Anonymous Tissue Archive, is involved with projects investigating the prevalence of variant CJD (vCJD) in the English population. This work is supported by translational research aimed at developing more sensitive and specific tests for the detection of the abnormal prion protein responsible for vCJD.

The TSE unit is also interested in the discovery and characterisation of unrecognised and novel viruses, especially those that may be responsible for encephalitis of unknown aetiology.

TSE are a class of diseases characterised by the appearance of a misfolded form of a cellular protein, known as the prion protein or PrPC. The misfolded form of this prion protein is called PrPSc or PrPres or PrPTSE or PrPCJD.

Examples of TSE diseases are Creutzfeldt-Jakob disease (CJD) in human, bovine spongiform encephalopathy in cattle and scrapie in sheep. The TSE unit manages the laboratory aspects of the National Anonymous Tissue Archive.

Laboratory tests for CJD

Western blotting

Laboratory diagnosis of CJD is dependent on demonstration of the presence of the protease resistant form of the prion protein, PrPCCJD (also referred to as PrPSc, PrPDIS, PrPTSE, and PrPres).

Screening for the presence of PrPCJD may be done by enzyme immunoassay (EIA) testing, but confirmation requires the more specific tests of Western blotting (WB) or immunohistochemistry (IHC). Please contact the laboratory for more information about these tests.

Prion gene polymorphism

A methionine/valine polymorphism at codon 129 of the ‘PRNP’ gene is associated with the clinical course of CJD. This genotyping can be done by PCR amplification of the ‘PRNP’ gene and subsequent digestion with the restriction enzyme ‘Nsp1’ (PCR-RFLP). Please contact the laboratory if further information is required about this test.